1. Field of the Invention
This invention relates to an ink cartridge used as an ink supply source of an ink jet printer and, in particular, to an ink cartridge comprising a configuration adequate for recycling and a configuration adequate for miniaturization. The present invention also relates to an ink jet printer using the above-described ink cartridge.
2. Description of the Related Art
A known ink supply mechanism of an ink jet printer is as follows An ink supply needle is placed in an ink cartridge placement part formed in an ink jet printer and, if an ink cartridge is placed so that the ink supply needle is inserted into an ink outlet formed in the ink cartridge, ink stored in the ink cartridge can be supplied to an ink jet head of the ink jet printer.
The ink cartridges used with such an ink jet printer are disclosed in JP-A-63-116833, JP-A-5-162333, JP-A-11-70672, etc. For example, the ink cartridge disclosed in JP-A-11-70672 comprises a cartridge case housing an ink back and a waste-ink absorption material, and a detection plate—for detecting when the amount of ink, remaining in the ink bag, gets low—is attached to the ink bag.
Some ink jet printers require two or more ink cartridges. For example, ink cartridges housing ink bags storing different color inks need to be placed in an ink jet printer for executing color printing.
However, if two ink cartridges are placed in the ink jet printer, it becomes cumbersome to attach and detach the ink cartridges and the ink cartridge placement part is upsized.
Thus, to simplify the ink cartridge placement operation and miniaturize the ink cartridge placement part, an ink cartridge housing two or more ink bags may be used. In this case, to make it possible to house the ink bags at the determined positions, and possible precisely to detect the amount of ink remaining in each ink bag by means of a detection plate attached thereto, the cartridge case may be divided into two partitions by a partition plate so that the ink bags separately are housed in the partitions.
However, to use the ink cartridge housing a plurality of ink bags, if any one of the ink bags becomes empty of ink, the ink cartridge needs to be replaced regardless of how much ink remains in any other ink bag. Therefore, it is extremely uneconomical to replace the ink cartridge if a large amount of ink remains in any ink bag other than the empty one. Generally, black ink is consumed in larger quantities than is colored ink and, thus, the ink cartridge must be replaced without entirely consuming the colored ink.
On the other hand, in recent years, for environmental protection, it has been desired that in so far as possible an ink cartridge be made up of recyclable parts. From this viewpoint, to recycle a cartridge case, it is desired that the cartridge case designed for easy disassembling.